Lignin-based surfactants

ABSTRACT

Methods for converting waste streams from the wood pulping industry to high-value surfactants are described. For example, isolated lignin and lignosulfonate or waste streams containing lignin and lignosulfonate can be directly converted to surfactants, or they can be first converted to methylol derivatives and treated with further reagents to produce surfactants.

CLAIM OF PRIORITY

This application is a continuation application of U.S. patentapplication Ser. No. 13/698,776, filed Nov. 19, 2012 entitled“LIGNIN-BASED SURFACTANTS,” which is a national phase application under35 U.S.C. §371 of International Application No. PCT/US2012/028022, filedMar. 7, 2012 and entitled “LIGNIN-BASED SURFACTANTS,” the disclosure ofwhich is incorporated by reference in its entirety and for all purposes.

BACKGROUND

Lignin, which represents 15-35% of wood, is the most abundant renewableorganic material on the earth. The pulping industry separates cellulosefrom the wood composition resulting in lignin and hemicellulose wasteby-products known as black liquor and spent pulp liquor. In the sulphiteprocess, the main by-product contained in the spent pulp liquor islignosulphonate. With each ton of pulping products producing 330-540 Kgof lignosulphonate, the global annual production capacity oflignosulphonate is about 1.8-2.0 million tons. Most of thelignosulphonate (66%) produced in pulping industries is burned as fueland 34% is treated and disposed. Using this waste stream as a fuelsource is inefficient, and releases large amounts of pollutants such asSO₂. Simple disposing of lignin, on the other hand, incurs a significantcost to the pulping industry.

Surfactants have myriad industrial and consumer uses. The worldproduction of surfactants in 1990 was 40 million tons which increased to60 million tons by 2010. Surfactants are used in soaps, detergents,dispersants for dyestuffs, admixtures for concrete as water reducers andplasticizers, emulsifiers for bitumen and agrochemicals such aspesticides and fungicides. They are also used in enhanced oil recoveryand oil drilling, wetting agents for textiles and pharmaceuticals,foaming agents, and demulsifying agents. Lignin-based surfactants couldreplace the current industrial manufacture of surfactants, particularlythose based on petrochemical resources, which use non-renewableresources, are expensive, and create non-biodegradable surfactants.

SUMMARY

This disclosure is not limited to the particular systems, devices andmethods described, as these may vary. The terminology used in thedescription is for the purpose of describing the particular versions orembodiments only, and is not intended to limit the scope. While variouscompositions and methods are described in terms of “comprising” variouscomponents or steps (interpreted as meaning “including, but not limitedto”), the compositions and methods can also “consist essentially of” or“consist of” the various components and steps, and such terminologyshould be interpreted as defining essentially closed-member groups.

Methods describe novel and simple processes comprising, among otherthings, the production of lignin-based surfactants. In some embodiments,methods of fabricating gemini surfactants from black liquor or spentliquor are described. The methods described herein may allow facileproduction of high-value products from waste stream from the pulpingindustry.

In an embodiment, a method of preparing a lignosulphonate methylol maycomprise contacting lignosulphonate with an aldehyde compound to producethe lignosulphonate methylol. In such embodiments, the source of thelignosulphonate may be sulphonated black liquor or spent pulp liquor.

In an embodiment, a method of preparing a lignin methylol may comprisecontacting lignin with an aldehyde compound at a pH of about 9 to about10 to produce the lignin methylol. In such embodiments, the source ofthe lignin may be black liquor.

In an embodiment, a method of preparing lignin methylol orlignosulphonate methylol from solid lignin or solid lignosulphonate maycomprise contacting lignin or lignosulphonate with an aldehyde compoundto produce lignin methylol or lignosulphonate methylol. In suchembodiments, the source of the lignosulphonate may be dried or dewateredblack liquor or spent pulp liquor.

In an embodiment, a method of preparing a surfactant may comprisecontacting lignin methylol or lignosulphonate methylol with a reagent toproduce the surfactant. In some embodiments, the reagent may comprise acarboxylic acid compound and the surfactant may be a lignin carboxylatecompound or a lignosulphonate carboxylate compound.

In an embodiment, a method of preparing a surfactant may comprisecontacting lignin with a reagent to produce the surfactant. In someembodiments, the reagent may comprise a carboxylic acid compound and thesurfactant may be a lignin carboxylate compound or a lignosulphonatecarboxylate compound.

In an embodiment, a method of preparing lignocarboxylate orlignosulphonate carboxylate may comprise contacting lignin orlignosulphonate with carbon dioxide to produce lignocarboxylate orlignosulphonate carboxylate.

In an embodiment, a surfactant may comprise a ligno phosphate compound,a lignosulphonate phosphate compound, a ligno ethanolamine compound, aligno sulphonate ethanolamine compound, a ligno polyhydroxycarboxylatecompound, a ligno sulphonate polyhydroxycarboxylate compound, alignopolycarboxylate compound, a lignosulphonate polycarboxylatecompound, a lignopolyhydroxycarboxylate compound, or a lignosulphonatepolyhydroxycarboxylate compound.

In some embodiments, a water-based resin may comprise a lignoepoxidecompound or a lignosulphonate epoxide compound. In other embodiments, apolyurethane product may comprise a lignourethane compound or alignosulphonate urethane compound. In further embodiments, a corrosioninhibitor, epoxy hardener, or a base for a hydrogel may comprise alignoamine compound or a lignosulphonate amine compound.

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin-based material with a carbohydrate or carbohydratederivative in the presence of a catalyst to produce the surfactant. Insome embodiments, the carbohydrate may be dextrose syrup, glucose syrup,or sucrose syrup. In other embodiments, the carbohydrate derivative maybe a polyhydroxy carboxylic acid, a hydroxyl polycarboxylic acid, anaminocarboxylic acid, a lithium, sodium, potassium, ammonium or calciumsalt thereof, or other natural carboxylic acid or salt thereof derivedby oxidation or fermentation of a carbohydrate.

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin-based material with an amino acid in a solvent toproduce the surfactant. In some embodiments, the amino acid is thesodium salt of arginine, leucine, lysine, glycine, glutamic acid,aspartic acid, contrition sulfate, or a combination thereof.

In an embodiment, a method of preparing a Gemini surfactant may comprisecontacting a lignin-based material with an amino acid in a solvent toproduce the Gemini surfactant, wherein the number of reacted methylolgroups with the amino acid may be two or more. In some embodiments, theamino acid may be the sodium salt of arginine, leucine, lysine, glycine,glutamic acid, aspartic acid, contrition sulfate, or a combinationthereof. In an embodiment, a method of preparing a Gemini surfactant maycomprise contacting a lignin-based material with an ethylene diaminederivative reactant to produce the Gemini surfactant, wherein the numberof reacted methylol groups with the ethylene diamine derivative may betwo or more. In some embodiments, the ethylene diamine derivativereactant may be ethylene diamine, diethylenetriamine,triethylenetetramine, tetraethylenepentamine, or polyethylenediamine.

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin-based material with polyethylene oxide terminatedwith epoxide groups in the presence of a catalyst to produce thesurfactant, wherein the number of reacted methylol groups with theethylene diamine derivative may be two or more. In some embodiments, thepolyethylene oxide terminated with epoxide groups has a molecular weightof about Mn=200 to about 600.

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin-based material with a silicon compound to producethe surfactant. In some embodiments, the silicon compound may be siliconoil terminated with active siloxane groups.

In an embodiment, a surfactant may comprise a lignoamino acid saltcompound, a lignosulphonate amino acid salt compound, a lignosiliconecompound, a lignosulphonate silicone compound, a ligno-functionalizedpolymer compound, a lignosulphonate-functionalized polymer compound, alignosaccharide compound, a lignosulphonate saccharide compound, alignoethylendiamine derivative compound, a lignosulphonateethylendiamine derivative compound, a lignoethanolamine derivativecompound, lignosulphonate ethanolamine derivative compounds, alignoglycoside, a lignosulphonate glycoside, or a combination thereof.

DETAILED DESCRIPTION

Described herein are methods for producing lignin-based surfactants. Insome embodiments, lignin-based starting material may be sourced fromwaste pulp streams including black liquor and spent pulp liquor. In someembodiments, lignin-based starting material may be converted tomethylols.

In an embodiment, a method of preparing a lignosulphonate methylol maycomprise contacting lignosulphonate with an aldehyde compound to producethe lignosulphonate methylol. The lignosulphonate may comprise spentpulp liquor, sulphonated black liquor, or a combination thereof. Thesolid content of the spent pulp liquor or sulphonated black liquor maybe adjusted to about 30% to about 60% by weight, to about 35% to about55% by weight, or to about 40% to about 50% by weight, or about 45% toabout 50% by weight, prior to contacting the lignosulphonate with thealdehyde compound. Specific examples of solid content include about 30%,about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, andranges between any two of these values (for example, from about 30% toabout 40%). The net active weight of lignin in the black liquor may bedetermined from the total organic content as measured by thermalanalysis of a sample of the black liquor dried at about 100° C. forabout 3 hours. The net active content ratio of the lignosulphonate tothe aldehyde compound may be about 1:1 to about 20:1, about 1:1 to about15:1, about 2:1 to about 15:1, about 2:1 to about 10:1, about 2:1 toabout 7.5:1, or about 2.5:1 to about 5:1. Specific examples of ratiosinclude about 1:1, about 2:1, about 2.5:1, about 5:1, about 7.5:1, about10:1, about 12.5:1, about 15:1, about 17.5:1, about 20:1, and rangesbetween any two of these values (for example, from about 10:1 to about17.5:1). In some embodiments, the aldehyde compound may be formaldehyde,paraformaldehyde, or trioxane.

In some embodiments, the lignosulphonate may be contacted with thealdehyde compound at a pH of about 8 to about 12, at a pH of about 9 toabout 11, or at a pH of about 9.5 to about 10.5. In some embodiments,the lignosulphonate may be contacted with the aldehyde compound at a pHof about 9 to about 10. Specific examples of pH include about 8, about8.5, about 9, about 9.5, about 10, about 10.5, about 11, about 11.5,about 12, and ranges between any two of these values (for example, fromabout 9 to about 11). The lignosulphonate may be contacted with thealdehyde compound at a temperature of about 50° C. to about 85° C.,about 55° C. to about 80° C., about 60° C. to about 75° C., or about 65°C. to about 70° C. In some embodiments, the lignosulphonate may becontacted with the aldehyde compound at a temperature of about 65° C. toabout 70° C. Specific examples of temperatures include about 50° C.,about 55° C., about 60° C., about 65° C., about 70° C., about 75° C.,about 80° C., about 85° C., and ranges between any two of these values(for example, from about 65° C. to about 80° C.). The lignosulphonatemay be contacted with the aldehyde compound for about 2 to about 5hours, about 2.5 to about 4.5 hours, or about 3 to about 4 hours. Insome embodiments, the lignosulphonate may be contacted with the aldehydecompound for about 3 to about 4 hours. In some embodiments, thelignosulphonate may be contacted with the aldehyde compound for about 3hours. Specific examples of contact time include about 2 hours, about2.5 hours, about 3 hours, about 3.5 hours, about 4 hours, about 4.5hours, about 5 hours, and ranges between any two of these values (forexample, from about 3.5 hours to about 4.5 hours). In some embodiments,higher temperatures may be synchronised with lower reaction times. Insome embodiments heating for more than about 3 hours may occur withreaction temperatures below about 60° C. At higher temperatures andlonger reaction times, the methylol resins may condense and form a bulkof highly crosslinked thermoset resin.

In some embodiments, the lignosulphonate methylol may compriselignosulphonate monomethylol, lignosulphonate dimethylol,lignosulphonate trimethylol, or lignosulphonate oligomethylol. Infurther embodiments, the lignosulphonate methylol may be cooled to about0° C. to about 10° C., or to about 0° C. to about 5° C. In furtherembodiments, the lignosulphonate methylol may be cooled to about 0° C.to about 10° C. In some embodiments, the lignosulphonate methylol may becooled to about 0° C. to about 5° C. Specific examples of cooledtemperatures include about 0° C., about 5° C., about 10° C., and rangesbetween any two of these values (for example, from about 5° C. to about10° C.).

The cooled lignosulphonate methylol may be neutralized with a pre-cooledacid, which may be at about 0° C. to about 10° C., and may be about 2%to about 15% or about 5% to about 10% acid, by weight. In someembodiments, the pre-cooled acid may be at about 0 to about 5° C.Specific cooled temperatures include about, about 0° C., about 5° C.,about 10° C., and ranges between any two of these values (for example,from about 0° C. to about 5° C.). Specific concentration examplesinclude about 2% by weight, about 5% by weight, about 7% by weight,about 10% by weight, and ranges between any two of these values (forexample, from about 5% to about 10%). In some embodiments, the cooledlignosulphonate methylol may be neutralized to a pH of about 6.8 toabout 7.2, to a pH of about 6.9 to about 7.1, or to a pH of about 7. Insome embodiments, the cooled lignosulphonate methylol may be neutralizedto a pH of about 7. In some embodiments, the pre-cooled acid may bephosphoric acid, paratoluenesulphonic acid, hydroxy acetic acid,gluconic acid, a hydroxypolycarboxylic acid, or a combination thereof.

In some embodiments, the neutralized, cooled, lignosulphonate methylolmay be isolated, and the separated lignosulphonate methylol may bedissolved in at least one alcohol. In some embodiments, the alcohol maybe selected from ethanol, methylated spirits, and isobutanol. In furtherembodiments, the lignosulphonate methylol may be dried. In someembodiments, the alcohol may be evaporated under reduced pressure toproduce the lignosulphonate methylol as a solid residue, or semi-solidviscous product, or viscous product. In some embodiments, thelignosulphonate methylol may be dried with molecular sieves beforeevaporation of the solvent.

In another embodiment, a method of preparing a lignin methylol maycomprise contacting lignin with an aldehyde compound at a pH of about 9to about 10 to produce the lignin methylol. The lignin may compriseblack liquor, and the solid content of the black liquor may be adjustedto about 40% to about 70% by weight, to about 45% to about 65% byweight, or to about 50% to about 60% by weight prior to contacting thelignin with the aldehyde compound. Specific examples of solid contentinclude about 40%, about 45%, about 50%, about 55%, about 60%, about65%, about 70%, and ranges between any two of these values (for example,from about 45% to about 60%). The net weight active content ratio of thelignin to the aldehyde compound may be about 1:1 to about 20:1. In someembodiments, the net active content ratio of the lignin to the aldehydecompound may be about 1:1 to about 20:1, about 1:1 to about 15:1, about2:1 to about 15:1, about 2:1 to about 10:1, about 2:1 to about 7.5:1, orabout 2.5:1 to about 5:1. Specific examples of ratios include about 1:1,about 2:1, about 2.5:1, about 5:1, about 7.5:1, about 10:1, about12.5:1, about 15:1, about 17.5:1, about 20:1, and ranges between any twoof these values. In some embodiments, the aldehyde compound may beformaldehyde, paraformaldehyde, or trioxane.

In some embodiments, the lignin may be contacted with the aldehydecompound at a temperature of about 50° C. to about 85° C., about 55° C.to about 80° C., about 60° C. to about 75° C., or about 65° C. to about70° C. In some embodiments, the lignin may be contacted with thealdehyde compound at a temperature of about 65° C. to about 70° C.Specific examples of temperatures include about 50° C., about 55° C.,about 60° C., about 65° C., about 70° C., about 75° C., about 80° C.,about 85° C., and ranges between any two of these values (for example,from about 55° C. to about 70° C.). The lignin may be contacted with thealdehyde compound for about 2 to about 5 hours, about 2.5 to about 4.5hours, or about 3 to about 4 hours. In some embodiments, the lignin maybe contacted with the aldehyde compound for about 3 to about 4 hours. Insome embodiments, the lignin may be contacted with the aldehyde compoundfor about 3 hours. Specific examples of contact time include about 2hours, about 2.5 hours, about 3 hours, about 3.5 hours, about 4 hours,about 4.5 hours, about 5 hours, and ranges between any two of thesevalues (for example, from about 3.5 hours to about 4.5 hours). In someembodiments, higher temperatures may be synchronised with lower reactiontimes. In some embodiments, heating for more than about 3 hours mayoccur with reaction temperatures below about 60° C. At highertemperatures and longer reaction times, the methylol resins may condenseand form a bulk of highly crosslinked thermoset resin. In someembodiments, the lignin may be contacted with the aldehyde compound at apH of about 10. Specific examples of pH include about 8, about 8.5,about 9, about 9.5, about 10, about 10.5, and ranges between any two ofthese values (for example, from about 9 to about 10).

In some embodiments, the lignin methylol may comprise ligninmonomethylol, lignin dimethylol, lignin trimethylol, or ligninoligomethylol. In further embodiments, the lignin methylol may be cooledto about 0° C. to about 10° C., or to about 0° C. to about 5° C. Infurther embodiments, the lignin methylol may be cooled to about 0° C. toabout 10° C. In some embodiments, the lignin methylol may be cooled toabout 0° C. to about 5° C. Specific examples of cooled temperaturesinclude about 0° C., about 5° C., about 10° C., about 15° C., and rangesbetween any two of these values (for example, from about 5° C. to about10° C.). The cooled lignin methylol may be neutralized with a pre-cooledacid, which may be at about 0° C. to about 10° C., and may be about 2%to about 10% or about 5% to about 10% acid, by weight. In someembodiments, the pre-cooled acid may be at about 0 to about 5° C.Specific pre-cooled temperatures include about 0° C., about 0° C., about5° C., about 10° C., and ranges between any two of these values (forexample, from about 0° C. to about 5° C.). Specific concentrationexamples include about 2% by weight, about 5% by weight, about 7% byweight, about 10% by weight, and ranges between any two of these values(for example, from about 5% to about 7%). In some embodiments, thecooled lignin methylol may be neutralized to a pH of about 6.8 to about7.2, to a pH of about 6.9 to about 7.1, or to a pH of about 7. In someembodiments, the cooled lignin methylol may be neutralized to a pH ofabout 7. In some embodiments, the pre-cooled acid may be phosphoricacid.

In some embodiments, the neutralized, cooled, lignin methylol may beisolated, and the separated lignin methylol may be dissolved in at leastone alcohol. In some embodiments, the alcohol may be selected fromethanol, methylated spirits and isobutanol. In further embodiments, thelignin methylol may be dried. In some embodiments, the alcohol may beevaporated under reduced pressure to produce the lignin methylol as asolid residue, or semi-solid viscous product, or viscous product. Insome embodiments, the lignosulphonate methylol may be dried withmolecular sieves.

In an additional embodiment, a method of preparing lignin methylol orlignosulphonate methylol from solid lignin or solid lignosulphonate maycomprise dissolving the lignin or lignosulphonate and contacting thedissolved lignin or lignosulphonate with an aldehyde compound to producethe lignin methylol or lignosulphonate methylol. The lignin orlignosulphonate may comprise spent pulp liquor, sulphonated blackliquor, black liquor, or a combination thereof. In some embodiments, thelignin or lignosulphonate may be dissolved in a base solution. In theseembodiments, the base solution may be about 10% to about 20% by weight,about 12.5% to about 15% by weight sodium hydroxide. The solid contentof the spent pulp liquor or sulphonated black liquor may be adjusted toabout 40% to about 70% by weight, to about 45% to about 65% by weight,or to about 50% to about 60% by weight prior to contacting thelignosulphonate with the aldehyde compound. Specific examples of solidcontent include about 40%, about 45%, about 50%, about 55%, about 60%,about 65%, about 70%, and ranges between any two of these values (forexample, from about 55% to about 65%). In some embodiments, the netweight active content ratio of the lignin or lignosulphonate to thealdehyde compound may be about 1:1 to about 20:1. In some embodiments,the net active content ratio of the lignin or lignosulphonate to thealdehyde compound may be about 1:1 to about 20:1, about 1:1 to about15:1, about 2:1 to about 15:1, about 2:1 to about 10:1, about 2:1 toabout 7.5:1, or about 2.5:1 to about 5:1. Specific examples of ratiosinclude about 1:1, about 2:1, about 2.5:1, about 5:1, about 7.5:1, about10:1, about 12.5:1, about 15:1, about 17.5:1, about 20:1, and rangesbetween any two of these values (for example, from about 2:1 to about7.5:1). In some embodiments, the aldehyde compound may be formaldehyde.

In some embodiments, the lignin or lignosulphonate may be contacted withthe aldehyde compound at a pH of about 9 to about 10. In someembodiments, the lignin or lignosulphonate may be contacted with thealdehyde compound at a pH of about 10. Specific examples of pH includeabout 8, about 8.5, about 9, about 9.5, about 10, about 10.5 and rangesbetween any two of these values (for example, from about 9 to about 10).The lignin or lignosulphonate may be contacted with the aldehydecompound at a temperature of about 50° C. to about 85° C., about 55° C.to about 80° C., about 60° C. to about 75° C., or about 65° C. to about70° C. In some embodiments, the lignin or lignosulphonate may becontacted with the aldehyde compound at a temperature of about 65° C. toabout 70° C. Specific examples of temperatures include about 50° C.,about 55° C., about 60° C., about 65° C., about 70° C., about 75° C.,about 80° C., about 85° C., and ranges between any two of these values(for example, from about 55° C. to about 80° C.). The lignin orlignosulphonate may be contacted with the aldehyde compound for about 2to about 5 hours, about 2.5 to about 4.5 hours, or about 3 to about 4hours. In some embodiments, the lignin or lignosulphonate may becontacted with the aldehyde compound for about 3 to about 4 hours. Insome embodiments, the lignin or lignosulphonate may be contacted withthe aldehyde compound for about 3 hours. Specific examples of contacttime include about 2 hours, about 2.5 hours, about 3 hours, about 3.5hours, about 4 hours, about 4.5 hours, about 5 hours, and ranges betweenany two of these values (for example, from about 3.5 hours to about 4.5hours). In embodiments, higher temperatures may be synchronised withlower reaction times. In some embodiments, heating for more than about 3hours may occur with reaction temperatures below about 60° C. At highertemperatures and longer reaction times, the methylol resins may condenseand form a bulk of highly crosslinked thermoset resin.

In some embodiments, the lignosulphonate methylol may compriselignosulphonate monomethylol, lignosulphonate dimethylol,lignosulphonate trimethylol, or lignosulphonate oligomethylol, and thelignin methylol may be lignin monomethylol, lignin dimethylol, lignintrimethylol, or lignin oligomethylol. In further embodiments, the ligninmethylol or lignosulphonate methylol may be cooled to about 0° C. toabout 10° C. In further embodiments, the lignin methylol orlignosulphonate methylol may be cooled to about 0° C. to about 10° C.,or to about 0° C. to about 5° C. In some embodiments, the ligninmethylol or lignosulphonate methylol may be cooled to about 0° C. toabout 5° C. Specific examples of cooled temperatures include about 0°C., about 5° C., about 10° C., and ranges between any two of thesevalues (for example, from about 5° C. to about 10° C.). The cooledlignin methylol or lignosulphonate methylol may be neutralized with apre-cooled acid, which may be at about 0° C. to about 10° C., and may beabout 2% to about 7.5% acid, by weight. In some embodiments, thepre-cooled acid may be at about 0 to about 5° C. Specific pre-cooledtemperatures include about 0° C., about 5° C., about 10° C., and rangesbetween any two of these values (for example, from about 5° C. to about10° C.). Specific concentration examples include about 2% by weight,about 5% by weight, about 7% by weight, about 10% by weight, and rangesbetween any two of these values (for example, from about 5% to about10%). In some embodiments, the cooled lignin methylol or lignosulphonatemethylol may be neutralized to a pH of about 6.8 to about 7.0, to a pHof about 6.9 to about 7.0, or to a pH of about 7. In some embodiments,the cooled lignin methylol or lignosulphonate methylol may beneutralized to a pH of about 7. In some embodiments, the pre-cooled acidmay be phosphoric acid.

In some embodiments, the neutralized, cooled, lignin methylol orlignosulphonate methylol may be isolated, and the separated ligninmethylol or lignosulphonate methylol may be dissolved in an alcohol. Insome embodiments, the alcohol may be selected from ethanol, methylatedspirits and isobutanol. In further embodiments, the lignin methylol orlignosulphonate methylol may be dried. In some embodiments, the alcoholmay be evaporated under reduced pressure to produce the lignin methylolor lignosulphonate methylol as a solid residue, or semi-solid viscousproduct, or viscous product. In some embodiments, the lignin methylol orlignosulphonate methylol may be dried with molecular sieves beforeevaporating the solvent.

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin methylol or lignosulphonate methylol with a reagentto produce the surfactant. In some embodiments, the reagent may comprisea hydroxycarboxylic acid compound, polyhydroxycarboxylic acid, ahydroxylamine compound, isocyanate terminated polymers, an aminecompound, a phosphate compound, epichlorohydrine, or sodium bisulphite.

In some embodiments, the lignin methylol or lignosulphonate methylol maybe contacted with the reagent at about 20° C. to about 60° C., at about25° C. to about 45° C., or at about 30° C. to about 35° C. In someembodiments, the lignin methylol or lignosulphonate methylol may becontacted with the reagent at about 30° C. to about 35° C. In someembodiments, the lignin methylol or lignosulphonate methylol may becontacted with the reagent at about 30° C. Specific examples oftemperatures include about 20° C., about 25° C., about 30° C., about 35°C., about 40° C., about 45° C., about 50° C., about 60° C., and rangesbetween any two of these values (for example, from about 25° C. to about35° C.). In some embodiments, the lignin methylol or lignosulphonatemethylol may be contacted with the reagent for about 1 hour to about 4hours, about 1.5 hours to about 3 hours, or about 2 hours. In someembodiments, the lignin methylol or lignosulphonate methylol may becontacted with the reagent for about two hours at about 30° C. Specificexamples of contact time include about 1 hour, about 1.5 hours, about 2hours, about 2.5 hours, about 3 hours, about 4 hours, about 5 hours, andranges between any two of these values (for example, from about 1.5hours to about 2.5 hours). Contact time may be determined by routinetests to indicate reaction completion which may be dependent on thereaction temperature and the reagent.

In further embodiments, the lignin methylol or lignosulphonate methyloland the reagent may be refluxed for about 30 minutes to about 120minutes, about 40 minutes to about 100 minutes, or about 60 minutes toabout 80 minutes. In some embodiments, the lignin methylol orlignosulphonate methylol and the reagent may be refluxed for about 1hour. Specific examples of reflux time include about 1 hour, about 1.5hours, about 2 hours, about 2.5 hours, about 3 hours, about 4 hours,about 5 hours, and ranges between any two of these values (for example,from about 3 hours to about 5 hours). In some embodiments, the reactionproducts may be neutralized with a basic solution. In some embodiments,the basic solution may be sodium hydroxide or calcium hydroxide at about2% to about 20% by weight, about 5% to about 20% by weight, or about 10%to about 20% by weight.

In some embodiments where the reagent comprises at least one carboxylicacid compound, the surfactant may be a lignin carboxylate compound or alignosulphonate carboxylate compound. In some embodiments, thecarboxylic acid compound may comprise a polycarboxylic acid, ahydroxycarboxylic acid, hydroxydicarboxylic acid, orpolyhydroxycarboxylic acid. In other embodiments, the carboxylic acidcompound may comprise gluconic acid, citric acid, tartaric acid,hydroxybutyric acid, hydroxyacetic acid, hydroxymalonic acid,hydroxysuccinic acid, or hydroxyglutamic acid. In some embodiments wherethe reagent comprises a hydroxyamino compound, the surfactant maycomprise a lignoethanolamine compound or a lignosulphonate ethanolaminecompound. In some embodiments, the hydroxylamine compound may comprisemonoethanolamine, diethanolamine, triethanolamine, or hydroxyl amine.

In some embodiments where the reagent comprises an isocyante terminatedpolymer, the surfactant may comprise a lignourethane compound or alignosulphonate urethane compound as foamed hydrogel water stop product.In some embodiments where the reagent comprises an amine compound, thesurfactant may comprise a lignoamine compound or a lignosulphonate aminecompound. In some embodiments where the reagent comprises a phosphatecompound, the surfactant may comprise a lignophosphate compound or alignosulphonate phosphate compound. In some embodiments where thereagent comprises epichlorohydrine, the surfactant may comprise a waterbased lignoepoxy compound or a lignosulphonate epoxy compound. In someembodiments where the reagent comprises sodium bisulphite, thesurfactant may comprise a lignosulphonate compound.

In another embodiment, a method of preparing a surfactant may comprisecontacting lignin with a reagent in a lignin/reagent reaction mixture toproduce the surfactant. In some embodiments, the reagent may comprise acarboxylic acid compound, a hydroxyamino compound, an isocyanteterminated polymer, an amine compound, a phosphate compound,epichlorohydrine, or sodium bisulphite. In some embodiments, the ligninmay be in the form of black liquor. In these embodiments, the solidcontent of the black liquor may be adjusted to about 40% to about 70% byweight, to about 45% to about 65% by weight, or to about 50% to about60% by weight prior to contacting the lignin with a reagent. Specificexamples of solid content include about 40%, about 45%, about 50%, about55%, about 60%, about 65%, about 70%, and ranges between any two ofthese values (for example, from about 55% to about 65%).

In some embodiments, the lignin may be contacted with the reagent atabout 20° C. to about 60° C., at about 25° C. to about 45° C., or atabout 30° C. to about 35° C. In some embodiments, the lignin may becontacted with the reagent at about 30° C. to about 35° C. In someembodiments, the lignin may be contacted with the reagent at about 30°C. Specific examples of temperatures include about 20° C., about 25° C.,about 30° C., about 35° C., about 40° C., about 45° C., about 50° C.,about 60° C., and ranges between any two of these values (for example,from about 25° C. to about 35° C.). In some embodiments, the lignin maybe contacted with the reagent for about 1 hour to about 4 hours, about1.5 hours to about 3 hours, or about 2 hours. In some embodiments, thelignin may be contacted with the reagent for about two hours at about30° C. Specific examples of contact time include about 1 hour, about 1.5hours, about 2 hours, about 2.5 hours, about 3 hours, about 4 hours,about 5 hours, and ranges between any two of these values (for example,from about 2.5 hours to about 4 hours).

In further embodiments, the lignin/reagent reaction mixture may berefluxed for about 30 minutes to about 120 minutes, about 40 minutes toabout 100 minutes, or about 60 minutes to about 80 minutes. In someembodiments, the lignin/reagent reaction mixture may be refluxed forabout 1 hour. Specific examples of reflux time include about 1 hour,about 1.5 hours, about 2 hours, and ranges between any two of thesevalues (for example, from about 1.5 hours to about 2 hours). In someembodiments, the lignin/reagent reaction mixture may be neutralized witha basic solution. In some embodiments, the basic solution may be sodiumhydroxide or calcium hydroxide at about 2% to about 20% by weight, about5% to about 20% by weight, or about 10% to about 20% by weight.

In some embodiments where the reagent comprises at least one carboxylicacid compound, the surfactant may be a lignin carboxylate compound. Insome embodiments, the carboxylic acid compound may comprise at least onepolycarboxylic acid, a hydroxycarboxylic acid, hydroxydicarboxylic acid,polyhydroxycarboxylic acid, or combinations thereof. In otherembodiments, the carboxylic acid compound may comprise gluconic acid,citric acid, tartaric acid, hydroxybutyric acid, hydroxyacetic acid,hydroxymalonic acid, hydroxysuccinic acid, hydroxyglutamic acid, orcombinations thereof. In some embodiments where the reagent comprises ahydroxyamino compound, the surfactant may comprise a lignoethanolaminecompound. In some embodiments, the hydroxylamino compound may comprisemonoethanolamine, diethanolamine, triethanolamine, hydroxyl amine, orcombinations thereof. In some embodiments where the reagent comprises anisocyante terminated polymer, the surfactant may comprise alignourethane compound as a foamed hydrogel water stop product. In someembodiments where the reagent comprises an amine compound, thesurfactant may comprise a lignoamine compound. In some embodiments wherethe reagent comprises a phosphate compound, the surfactant may comprisea lignophosphate compound. In some embodiments where the reagentcomprises epichlorohydrine, the surfactant may comprise a water basedlignoepoxy compound. In some embodiments where the reagent comprisessodium bisulphite, the surfactant may comprise a lignosulphonatecompound with a high degree of sulphonation.

In another embodiment, a method of preparing lignocarboxylate orlignosulphonate carboxylate may comprise contacting lignin orlignosulphonate with carbon dioxide to produce lignocarboxylate orlignosulphonate carboxylate. In some embodiments, the carbon dioxide maybe a gas or in the form of dry ice. In other embodiments, the carbondioxide may be carbon dioxide adducts formed by carbon dioxide absorberswhich are formed in the reclaiming processes of carbon dioxide from theatmosphere or from industrial sources. In some embodiments, the ligninmay comprise black liquor and the lignosulphonate may be in the form ofspent pulp liquor, sulphonated black liquor, or a combination thereof.In some embodiments, the solid content of the black liquor, spent pulpliquor or sulphonated black liquor may be adjusted to may be adjusted toabout 40% to about 70% by weight, to about 45% to about 65% by weight,or to about 50% to about 60% by weight prior to contacting the lignin orlignosulphonate with carbon dioxide. Specific examples of solid contentinclude about 40%, about 45%, about 50%, about 55%, about 60%, about65%, about 70%, and ranges between any two of these values (for example,from about 55% to about 65%).

In some embodiments, the lignin or lignosulphonate may be contacted withthe carbon dioxide under a pressure of about 90 atm to about 150 atm,about 100 atm to about 130 atm, or about 100 atm to about 120 atm. Insome embodiments, the lignin or lignosulphonate may be contacted withthe carbon dioxide under a pressure of about 100 atm. In someembodiments, the lignin or lignosulphonate may be contacted with thecarbon dioxide at a temperature of about 100° C. to about 160° C., about110° C. to about 140° C., or about 120° C. to about 130° C. In someembodiments, the lignin or lignosulphonate may be contacted with thecarbon dioxide at a temperature of about 125° C. Specific examples oftemperatures include about 100° C., about 115° C., about 120° C., about125° C., about 130° C., about 140° C., about 150° C., about 160° C., andranges between any two of these values (for example, from about 120° C.to about 140° C.). In some embodiments, the lignin or lignosulphonatemay be contacted with the carbon dioxide for about 2 hours to about 8hours, about 3 hours to about 7 hours, or about 4 hours to about 6hours. In some embodiments, the lignin or lignosulphonate may becontacted with the carbon dioxide for about 5 hours. Specific examplesof contact time include about 2 hours, about 3 hours, about 4 hours,about 4.5 hours, about 5 hours, about 5.5 hours, about 6 hours, about 7hours, about 8 hours, and ranges between any two of these values (forexample, from about 4.5 hours to about 5.5 hours). In some embodiments,the contacting may take place in an autoclave with a rotating mix.

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin-based material with a carbohydrate or carbohydratederivative in the presence of a catalyst to produce the surfactant. Insome embodiments, the lignin-based material may be lignin methylol,lignosulphonate methylol, lignin, lignosulphonate, or any combinationthereof. In some embodiments, the carbohydrate may be dextrose syrup,glucose syrup, or sucrose syrup. In these embodiments, the source of thecarbohydrate may be include, but is not limited to, dates, sorbitol,maltose, or a combination thereof. In some embodiments, the carbohydratederivative may be: a polyhydroxy carboxylic acid; a hydroxylpolycarboxylic acid, including but not limited to, hydroxymonocarboxylic acids, hydroxydicarboxylic acids, hydroxytetracarboxylicacids, and hydroxypolycarboxylic acids; an aminocarboxylic acid,including but limited to, aminomono carboxylic acids, aminodi carboxylicacids, aminotri carboxylic acids, aminotetra carboxylic acids; alithium, sodium, potassium, ammonium or calcium salt thereof; or othernatural carboxylic acid or salt thereof derived by oxidation orfermentation of a carbohydrate. Specific examples of carbohydrates andcarbohydrate derivatives include sodium gluconate, sodium glutamate,hydroxyl sodium acetate, citric acid, tartaric acid, hydroxyl aceticacid, gluconic acid, and glutamic acid. The carbohydrates andcarbohydrate derivatives may be obtained or derived from naturalresources including, for example, dates, sugar cane waste, olive oilwastes, and others sugar and oil containing wastes.

In some embodiments, the ratio of lignin-based material to carbohydrateor carbohydrate derivative may be about 1:1 to about 1:1.2 based onmoles of methylol groups in the lignin-based material to moles of thecarbohydrate or carbohydrate derivative. In some embodiments, the ratioof lignin-based material to carbohydrate or carbohydrate derivative maybe about 1:1. Specific examples of ratios include about 1:1.1, about1:1.2, about 1:1.3 molar ratio and ranges between any two of thesevalues (for example, from about 1:1 to about 1:1.1). In someembodiments, the catalyst may be phosphoric acid or paratoluenesulphonic acid.

In some embodiments, contacting the lignin-based material with thecarbohydrate or carbohydrate derivative occurs with heating by amicrowave or in a water bath. In some embodiments, the microwave may bea kitchen type microwave with an output of about 1100 watts to about1500 watts. In some embodiments, the lignin-based material may becontacted with the carbohydrate or carbohydrate derivative at about 40°C. to about 60° C., at about 45° C. to about 55° C. In some embodiments,the lignin-based material may be contacted with the carbohydrate orcarbohydrate derivative at about 50° C. Specific examples oftemperatures include about 40° C., about 45° C., about 50° C., about 55°C., about 60° C., and ranges between any two of these values (forexample, from about 40° C. to about 60° C.). In some embodiments, thelignin-based material may be contacted with the carbohydrate orcarbohydrate derivative for about 0.5 hour to about 2 hours, about 1hour to about 1.5 hours. In some embodiments, the lignin-based materialmay be contacted with the carbohydrate or carbohydrate derivative forabout 0.5. Specific examples of contact time include about 0.5 hours,about 1 hours, about 1.0 hours, about 1.5 hours, about 4 hours, about 5hours, and ranges between any two of these values (for example, fromabout 0.5 hours to about 2 hours).

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin-based material with an amino acid in a solvent toproduce the surfactant. In some embodiments, the lignin-based materialmay be lignin methylol, lignosulphonate methylol, lignin, or anycombination thereof. In some embodiments, the amino acid may be thesodium salt of arginine, leucine, lysine, glycine, glutamic acid,aspartic acid, contrition sulfate, or a combination thereof. In someembodiments, the ratio of lignin-based material to amino acid may beabout 1:1 to about 1:1.3 based on moles of methylol groups in thelignin-based material to moles of the amino acid. In some embodiments,the ratio of lignin-based material to amino acid may be about 1:1.1.Specific examples of ratios include about 1:1, about 1:1.2, about 1:1.3,and ranges between any two of these values (for example, from about 1:1to about 1:1.2). In some embodiments, the solvent may be triethylamineor a mixture of triethylamine with n-butanol.

In some embodiments, contacting the lignin-based material with the aminoacid occurs at about 50° C. to about 70° C. for about 3 hours to about4.0 hours with efficient mixing. In some embodiments, contacting thelignin-based material with the amino acid occurs at about 60° C. forabout 3 hours with efficient mixing. Specific examples of temperaturesinclude about 50° C., about 55° C., about 60° C., about 65° C., about70° C. and ranges between any two of these values (for example, fromabout 60° C. to about 65° C.). Specific examples of contact time includeabout 3 hours, about 3.2 hours, about 3.4 hours, about 3.5 hours, about4 hours and ranges between any two of these values (for example, fromabout 3.0 hours to about 4.0 hours).

Gemini surfactants represent a class of surfactants made up of twoidentical or different amphiphilic moieties having the structure ofconventional surfactants connected by a spacer group. The spacer may behydrophobic (aliphatic or aromatic) or hydrophilic (polyether), short(two methylene groups) or long (up to 20 and more methylene groups),rigid (stilbene) or flexible (polymethylene chain). In an embodiment, amethod of preparing a Gemini surfactant may comprise contacting alignin-based material with an amino acid in a solvent to produce theGemini surfactant, wherein the number of reacted methylol groups inlignin molecule with the amino acid may be two or more. In someembodiments, the lignin-based material may be lignin methylol,lignosulphonate methylol, or any combination thereof. In someembodiments, the amino acid may be the sodium salt of: arginine,leucine, lysine, glycine, glutamic acid, aspartic acid, contritionsulfate, or a combination thereof. In some embodiments, the ratio oflignin-based material to amino acid may be from about 1:1 to about 1:1.3based on moles of methylol groups in the lignin-based material to theamino acid. In some embodiments, the ratio of lignin-based material toamino acid may be about 1:1. Specific examples of ratios include about1:1, about 1:1.1, about 1:1.2, about 1:1.3, and ranges between any twoof these values (for example, from about 1:1 to about 1:1.2). In someembodiments, the solvent may be triethylamine, or a mixture oftriethylamine with n-butanol.

In some embodiments, contacting a lignin-based material with an aminoacid occurs at about 50° C. to about 70° C. for about 3 hours to about4.0 hours. In some embodiments, contacting a lignin-based material withan amino acid occurs at about 60° C. for about 3 hours. Specificexamples of temperatures include about 50° C., about 55° C., about 60°C., about 65° C., about 70° C. and ranges between any two of thesevalues (for example, from about 60° C. to about 65° C.). Specificexamples of contact time include about 3 hours, about 3.2 hours, about3.4 hours, about 3.5 hours, about 4 hours, and ranges between any two ofthese values (for example, from about 3.0 hours to about 4.0 hours).

In an embodiment, a method of preparing a Gemini surfactant may comprisecontacting a lignin-based material with an ethylene diamine derivativereactant to produce the Gemini surfactant, wherein the number of reactedmethylol groups in a lignin molecule with the ethylene diaminederivative may be two or more. In some embodiments, the lignin-basedmaterial may be lignin methylol, lignosulphonate methylol, or anycombination thereof. In some embodiments, the ethylene diaminederivative reactant may be ethylene diamine, diethylenetriamine,triethylenetetramine, or tetraethylenepentamine or polyethylenediamine.In some embodiments, the ratio of lignin-based material to ethylenediamine reactant may be about 1:1 to about 1:1.3 based on moles ofmethylol groups in the lignin-based material to moles of the ethylenediamine derivatives. In some embodiments, the ratio of lignin-basedmaterial to ethylene diamine derivative reactant may be about 1:1.Specific examples of ratios include about 1:1, about 1:1.1, about 1:1.2,about 1:1.2, and ranges between any two of these values (for example,from about 1:1 to about 1:1.2).

In some embodiments, contacting the lignin-based material with theethylene diamine derivative occurs at about 50° C. to about 70° C. forabout 3 hours to about 4.0 hours. In some embodiments, contacting thelignin-based material with the ethylene diamine derivative occurs atabout 60° C. to about 70° C. for about 3 hours. Specific examples oftemperatures include about 50° C., about 60° C., about 65° C., about 70°C., and ranges between any two of these values (for example, from about60° C. to about 65° C.). Specific examples of contact time include about3 hours, about 3.2 hours, about 3.4 hours, about 3.5 hours, about 4hours and ranges between any two of these values (for example, fromabout 3.0 hours to about 4.0 hours).

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin-based material with polyethylene oxide terminatedwith epoxide groups in the presence of a catalyst to produce thesurfactant, wherein the number of reacted methylol groups with theethylene diamine derivative may be two or more. In some embodiments, thelignin-based material may be lignin methylol, lignosulphonate methylol,or any combination thereof. In some embodiments, the polyethylene oxideterminated with epoxide groups has a molecular weight (Mn) of about 200to about 600. In some embodiments, the ratio of lignin-based material topolyethylene oxide may be about 1:1 to about 1:1.3 based on moles ofmethylol groups in the lignin-based material to moles of thepolyethylene oxide. In some embodiments, the ratio of lignin-basedmaterial to polyethylene oxide may be about 1:1. Specific examples ofratios include about 1:1, about 1:1.1, about 1:1.2, about 1:1.2, andranges between any two of these values (for example, from about 1:1 toabout 1:1.2). In some embodiments, the catalyst may be phosphoric acid,p-toluene sulphonic acid, or diamino compounds such as ethylene diamineand its derivatives.

In some embodiments, contacting the lignin-based material with thepolyethylene oxide occurs at about 50° C. to about 70° C. for about 3 toabout 4 hours. Specific examples of temperatures include about 50° C.,about 55° C., about 60° C., about 65° C., about 70° C. and rangesbetween any two of these values (for example, from about 55° C. to about65° C.). Specific examples of contact time include about 3 hours, about3.2 hours, about 3.4 hours, about 3.5 hours, and ranges between any twoof these values (for example, from about 3.0 hours to about 4.0 hours).

In an embodiment, a method of preparing a surfactant may comprisecontacting a lignin-based material with a silicon compound to producethe surfactant. In some embodiments, the lignin-based material may belignin methylol, lignosulphonate methylol, or any combination thereof.In some embodiments, the silicon compound may be silicon oil terminatedwith active siloxane groups. Specific examples of active siloxanes maybe, but are not limited to, epoxide siloxanes and aziridine siloxanes.In some embodiments, the ratio of lignin-based material to siliconcompound may be about 1:1 about 1:1.3 based on moles of methylol groupsin the lignin-based material to moles of siloxanating agents. In someembodiments, the ratio of lignin-based material to silicon compound maybe about 1:1. Specific examples of ratios include about 1:1, about1:1.2, about 1:1.3, and ranges between any two of these values (forexample, from about 1:1 to about 1:1.2).

In some embodiments, contacting the lignin-based material with thesilicon compound occurs at about room temperature for about 6 hours toabout 12 hours. Specific examples of temperatures include about 20° C.,about 23° C., about 25° C., about 30° C., and ranges between any two ofthese values (for example, from about 23° C. to about 25° C.). Specificexamples of contact time include about 6 hours, about 8 hours, about 10hours, about 12 hours, and ranges between any two of these values (forexample, from about 8 hours to about 10 hours).

In an embodiment, a surfactant may comprise a lignoamino acid saltcompound, a lignosulphonate amino acid salt compound, a lignosiliconecompound, a lignosulphonate silicone compound, a ligno-functionalizedpolymer compound, a lignosulphonate-functionalized polymer compound, alignosaccharide compound, a lignosulphonate saccharide compound, alignoethylendiamine derivative compound, a lignosulphonateethylendiamine derivative compound, a lignoethanolamine derivativecompound, lignosulphonate ethanolamine derivative compounds, alignoglycoside, a lignosulphonate glycoside, or a combination thereof.

EXAMPLES Example 1: Conversion of Black Liquor-Sourced Lignin toMethylol Lignin

Black liquor (1 L) with 50% to 60% solid content and a pH range of 9 to13 was treated with varying amounts (100, 200, 400, 600, and 800 mL) ofa formaldehyde solution (36% to 38% formaldehyde content [wt./vol]) toachieve lignin:formaldehyde net ratios of 20:1, 10:1, 5:1, 3.6:1, and2.5:1. Each reaction was carried out in a five necked flanged topreaction vessel fitted with efficient mechanical stirrer immersed inthermo stated water bath. The effects of reaction pH, temperature, time,and reactant ratio on the concentration of methylols formed wereinvestigated. The concentration of methylol lignin was determined in thereaction mixture by colorimetric techniques using ceric ammonium nitrateand differential scanning calorimetry. Among the tested parameters, areaction time of 3 hours with a pH of 10, a temperature of 65-70° C.,and a lignin:formaldehyde net active content ratio of 5:1 gave thehighest concentration of ligno methylol derivatives. The obtained ligninmethylol derivatives could be used in situ or separated from thesolution and stabilized.

TABLE 1-1 Effect of weight ratio of lignin:aldehyde on the number ofmethylol groups per structural unit of lignin as determined bycolorimetric and DSC. Increase CH₂OH/ Wt. ratio Structural IncreaseLignin: Temperature Reaction unit of Average Number of Exp. aldehyde °C. time (h) pH lignin. of 3 exp CH₂OH C-1 to C-3 20:1  65-70 3.0 9-10 0.25-0.75 0.56 1.0 C-4 to C-6 10:1  65-70 3.0 9-10  1.54-1.87 1.75 2.0C-7 to C-9  5:1 65-70 3.0 9-10 2.59-3.4 2.83 3.0 C-10 to C-12 3.6:1*65-70 3.0 9-10 2.84-3.3 2.86 3.0 C-13 to C-15 2.5:1* 65-70 3.0 9-102.94-3.4 2.98 3.0 *Excess of unreacted formaldehyde was found in thereaction mixture

TABLE 1-2 Effect of reaction temperature on the number of methylolgroups per structural unit of lignin at weight ratio of lignin:aldehyde= 5:1. Increase CH₂OH/ Reac- Structural Average Increase Temp tion unitof of 3 Number Exp. ° C. time (h) pH lignin. exp of CH₂OH T-1 to T-350-60 3.0 9-10 0.32-0.67 0.51 1.0 T-4 to T-6 60-65 3.0 9-10 2.33-2.572.48 3.0 T-7 to T-9 65-70 3.0 9-10 2.89-3.4  2.93 3.0 T-10 to T-12 70-753.0 9-10 2.44-2.94 2.54 3.0 T-13 to T-15  75-80* 3.0 9-10 1.74-2.14 1.872.0 *Temperatures above 80° C. gave crosslinked products even for lowerreaction time.

TABLE 1-3 Effect of pH on the methylol groups per structural unit oflignin at weight ratio of lignin:aldehyde = 5:1 and reaction temperature= 65-70° C. Increase CH₂OH/ Average Increase Reaction Structural ofnumber Exp. time (h) pH unit of lignin. 3 exp of CH₂OH Al-1 to Al-3 3.08-9 0.22-0.48 0.45 — Al-4 to Al-6 3.0  9-10 2.89-3.4  2.93 3.0 Al-7 toAl-9 3.0 10-11 2.78-3.32 2.90 3.0 Al-10 to Al-12 3.0 11-12 2.01-2.642.54 3.0 Al-13 to 3.0 12-13 1.64-1.98 1.87 2.0 Al-15* *pH 13 and abovegave gel crosslinked products even for lower reaction time.

TABLE 1-4 Effect of reaction time on the number of methylol groups perstructural unit of lignin at weight ratio of lignin:aldehyde = 5:1, pH =9-10, and reaction temperature = 65-70° C. Increase CH₂OH/ AverageReaction Structural unit of Increase number Exp. time (h) of lignin. 3exp of CH₂OH t-1 to t-3 2.5 1.80-2.48 2.03 2 t-4 to t-6 3.0 2.89-3.4 2.93 3.0 t-7 to t-9 3.5 2.92-3.12 2.97 3.0 t-10 to t-12 4.0 2.85-3.102.90 3.0 t-13 to t 15 5.0 2.65-2.86 2.79 3.0 *Reaction time above 5hours gave crosslinked gel products.

Example 2: Purification and Stabilization of Lignin Methylol

The lignin methylol reaction products from Example 1 in each case werecooled to 0-5° C. and neutralized to pH 7 by adding a pre-cooled 10%phosphoric acid (at 5° C.). The viscous semi-solid lignin methylolproducts were separated from the aqueous solution, dissolved in ethanol,dried with molecular sieves, and either used directly after evaporatingethanol under reduced pressure or stabilized by alcohols for storage ina refrigerator for future use.

Example 3: Preparation and Separation of Methylol Lignin from SolidLignin Waste

Solid lignin (500 grams) from pulping waste was dissolved in 10-20%sodium hydroxide solution, the pH was adjusted to 9-10, with 50% to 60%solid content, and the solution was treated with formaldehyde atlignin:formaldehyde net ratios of 20:1, 10:1, 5:1, 3.6:1, and 2.5:1. Areaction time of 3 hours with a pH of 10, a temperature of 60-75° C.,and a lignin:formaldehyde net active content ratio of 5:1 gave 2.8methylol groups per lignin structural unit. (Typical values are shown inTables 1-1 to 1-4).

Example 4: Preparation of Methylol Lignosulphonate Derivatives.

Lignosulphonate pulping by product was adjusted to a pH of 10 with 50%to 60% solid content and was treated with varying amounts of aformaldehyde solution to achieve lignin:formaldehyde net ratios of 20:1,10:1, 5:1, 3.6:1, and 2.5:1.

Example 5: Preparation of Sodium Lignocarboxylate

One mole of a methylol lignin solution as prepared in Examples 1 or 2was treated with citric acid at 30° C. using equivalent moles tomethylol groups with mixing for two hours. The reaction mixture was thenrefluxed for one hour, cooled, and neutralized with a 20% sodiumhydroxide solution to obtain sodium lignocarboxylate.

Example 6: Preparation of Sodium Lignocarboxylatesulphonate

One mole of methylol ligno sulphonate as prepared in Example 4 wastreated with citric acid at 30° C. using equivalent moles to methylolgroups with mixing for two hours. The reaction mixture was then refluxedfor one hour, cooled, and neutralised with 20% sodium hydroxide solutionto obtain sodium lignocarboxylatesulphonate dual functionalitysurfactant.

Example 7: Preparation of Sodium Lignogluconate

One mole of a methylol lignin solution as prepared in Examples 1, or 2was treated with sodium gluconate or gluconic acid at 30° C. usingequivalent moles to methylol groups. When sodium gluconate was used asreactant, 10% gluconic acid as catalyst and co reactant was added to thereaction mixture. The reaction mixture was mixed for two hours, and wasthen refluxed for one hour, cooled, and neutralized with 20% sodiumhydroxide solution to obtain sodium lignogluconate surfactant.

Example 8: Preparation of Sodium Lignosulphonate Gluconate

One mole of a methylol lignosulphonate solution as prepared in Example 4was treated with sodium gluconate or gluconic acid at 30° C. usingequivalent moles to methylol groups. When sodium gluconate was used asreactant, 10% gluconic acid as catalyst and co reactant was added to thereaction mixture. The reaction mixture was mixed for two hours, and wasthen refluxed for one hour, cooled, and neutralized with 20% sodiumhydroxide solution to obtain sodium lignosulphonate gluconate assurfactant.

Example 9: Preparation of Lignocarboxylate from Black Liquor and CarbonDioxide

An autoclave reactor was charged with black liquor and solid carbondioxide (dry ice), and was then secured and heated to 125° C. at 100 atmpressure with mixing for five hours. The reaction mixture was cooled andthen the degree of carboxylation was determined by FTIR spectroscopycarried out on a purified sample. The quantitative analyses were basedon the peak height at 1750 cm⁻¹ related to carboxyl group. The productunderwent carboxylation as demonstrated by a 2-5% increase in the solidcontent after the carboxylation reactions which was in a good agreementwith the FTIR results.

Example 10: Reaction of Lignomethylol with Carbohydrates

Equimolar amounts of semi-viscous lignomethylol from Example 1 and eachof the following carbohydrate sources (dextrose syrup, glucose syrup andsucrose syrup from dates, sorbitol and maltose) were mixed together inthe presence of phosphoric acid as catalyst and heated in a 1500 Wmicrowave oven for 30 minutes. A homogenous viscous product wasobtained, which was partially soluble in water according to the sourceof lignomethylols and the number of methylol groups per lignin molecule.The soluble part was separated and its surfactant properties weredetermined including: dynamic and static surface tension, viscosity andcloud point. High molecular weight methylol lignin gave almost insolubleproducts (95%) and had excellent emulsifying and wetting properties.

Example 11: Reaction of Lignomethylol and Lignosulphonate Methylol withAmino Acids

Equimolar amounts of lignomethylol and lignosulphonate methylolderivatives from Example 1 were reacted with sodium salts of arginine,leucine, lysine, glycine, glutamic acid, aspartic acid and contritionsulphate using equivalent moles of amino acid sodium salt to methylolgroups in the presence of triethylamine as solvent. The reaction mixturewas heated on a water bath at 60° C. for three hours. The lignoaminoacidsalt surfactants obtained were separated, purified, and the generalefficiency of the surfactants were determined including: surface tensionmeasurement of water containing different concentrations of eachsurfactant, viscosity and cloud point.

Example 12: Preparation of Gemini Surfactants from Lignin-BasedMaterials and Amino Acids

In the presence of triethylamine as solvent, lignomethylol andlignosulphonate methylol derivatives with two or more methylol groupsper molecule from Example 1 were reacted with sodium salts of arginine,leucine, lysine, glycine, glutamic acid, aspartic acid and contritionsulphate in equimolar amounts based on moles of amino acid sodium saltto moles of methylol groups. The Gemini surfactants obtained wereseparated, purified, and the general efficiency of the surfactants weredetermined including: surface tension measurement of water containingdifferent concentrations of each surfactant, viscosity and cloud point.The surfactant efficiency of these surfactants was superior to that ofthose from Example 11.

Example 13: Preparation of Gemini Surfactants from Lignin-BasedMaterials and Ethylene Diamines

Lignomethylol and lignosulphonate methylol derivatives with two or moremethylol groups per molecule from Example 1 were reacted with a seriesof ethylene diamines (ethylene diamine, diethylenetriamine,triethylenetetramine and tetraethylenepentamine) by mixing equimolaramounts of each component based on moles of amino acid sodium salt tomoles of methylol groups and heating the mixture at 60-70 C for threehours. The Gemini surfactants obtained were separated, purified, and thegeneral efficiency of the surfactants were determined including: surfacetension measurement of water containing different concentrations of eachsurfactant, viscosity and cloud point.

Example 14: Reaction of Lignomethylol with Epoxide-TerminatedPolyethylene Oxide

Lignomethylols from Example 1 and polyethylene oxide terminated withepoxide groups (Mn=200-600) were combined using equivalent molar ratiosbased on moles of polyethylene oxide to moles of methylol groups in thepresence of phosphoric acid as catalyst and heated to 50-60° C. withcontinuous mixing for three hours. The surfactants obtained wereseparated, purified, and the general efficiency of the surfactants weredetermined including: surface tension measurement of water containingdifferent concentrations of each surfactant, viscosity and cloud point.

Example 15: Reaction of Lignomethylol with Silicon Oil

Lignomethylols from Example 1 and silicon oil terminated with activesiloxane groups were combined using equivalent molar ratios based onmoles of siloxane to moles of methylol groups with continuous mixing atroom temperature under dry conditions overnight. The surfactantsobtained were separated, purified, and the general efficiency of thesurfactants were determined including: surface tension measurement ofwater containing different concentrations of each surfactant, viscosityand cloud point.

The present disclosure is not to be limited in terms of the particularembodiments described in this application, which are intended asillustrations of various aspects. Many modifications and variations canbe made without departing from its spirit and scope, as will be apparentto those skilled in the art. Functionally equivalent methods andapparatuses within the scope of the disclosure, in addition to thoseenumerated herein, will be apparent to those skilled in the art from theforegoing descriptions. Such modifications and variations are intendedto fall within the scope of the appended claims. The present disclosureis to be limited only by the terms of the appended claims, along withthe full scope of equivalents to which such claims are entitled. It isto be understood that this disclosure is not limited to particularmethods, reagents, compounds, compositions or biological systems, whichcan, of course, vary. It is also to be understood that the terminologyused herein is for the purpose of describing particular embodimentsonly, and is not intended to be limiting.

With respect to the use of substantially any plural and/or singularterms herein, those having skill in the art can translate from theplural to the singular and/or from the singular to the plural as isappropriate to the context and/or application. The varioussingular/plural permutations may be expressly set forth herein for sakeof clarity.

It will be understood by those within the art that, in general, termsused herein, and especially in the appended claims (e.g., bodies of theappended claims) are generally intended as “open” terms (e.g., the term“including” should be interpreted as “including but not limited to,” theterm “having” should be interpreted as “having at least,” the term“includes” should be interpreted as “includes but is not limited to,”etc.). It will be further understood by those within the art that if aspecific number of an introduced claim recitation is intended, such anintent will be explicitly recited in the claim, and in the absence ofsuch recitation, no such intent is present. For example, as an aid tounderstanding, the following appended claims may contain usage of theintroductory phrases “at least one” and “one or more” to introduce claimrecitations. However, the use of such phrases should not be construed toimply that the introduction of a claim recitation by the indefinitearticles “a” or “an” limits any particular claim containing suchintroduced claim recitation to embodiments containing only one suchrecitation, even when the same claim includes the introductory phrases“one or more” or “at least one” and indefinite articles such as “a” or“an” (e.g., “a” and/or “an” should be interpreted to mean “at least one”or “one or more”); the same holds true for the use of definite articlesused to introduce claim recitations. In addition, even if a specificnumber of an introduced claim recitation is explicitly recited, thoseskilled in the art will recognize that such recitation should beinterpreted to mean at least the recited number (e.g., the barerecitation of “two recitations,” without other modifiers, means at leasttwo recitations, or two or more recitations). Furthermore, in thoseinstances where a convention analogous to “at least one of A, B, and C,etc.” is used, in general, such a construction is intended in the senseone having skill in the art would understand the convention (e.g., “asystem having at least one of A, B, and C” would include but not belimited to systems that have A alone, B alone, C alone, A and Btogether, A and C together, B and C together, and/or A, B, and Ctogether, etc.). It will be further understood by those within the artthat virtually any disjunctive word and/or phrase presenting two or morealternative terms, whether in the description, claims, or figure, shouldbe understood to contemplate the possibilities of including one of theterms, either of the terms, or both terms. For example, the phrase “A orB” will be understood to include the possibilities of “A” or “B” or “Aand B.”

In addition, where features or aspects of the disclosure are describedin terms of Markush groups, those skilled in the art will recognize thatthe disclosure is also thereby described in terms of any individualmember or subgroup of members of the Markush group.

As will be understood by one skilled in the art, for any and allpurposes, such as in terms of providing a written description, allranges disclosed herein also encompass any and all possible subrangesand combinations of subranges thereof. Any listed range can be easilyrecognized as sufficiently describing and enabling the same range beingbroken down into at least equal halves, thirds, quarters, fifths,tenths, etc. As a non-limiting example, each range discussed herein canbe readily broken down into a lower third, middle third and upper third,etc. As will also be understood by one skilled in the art all languagesuch as “up to,” “at least,” and the like include the number recited andrefer to ranges which can be subsequently broken down into subranges asdiscussed above. Finally, as will be understood by one skilled in theart, a range includes each individual member. Thus, for example, a grouphaving 1-3 substituents refers to groups having 1, 2, or 3 substituents.Similarly, a group having 1-5 substituents refers to groups having 1, 2,3, 4, or 5 substituents, and so forth.

What is claimed is:
 1. A method of preparing a surfactant, the methodcomprising contacting a lignin-based material containing one or moremethylol groups with an amino acid in a ratio of about 1:1 to about1:1.3 based on moles of the one or more methylol groups in thelignin-based material to moles of the amino acid in presence of asolvent selected from triethylamine, or a mixture of triethylamine withn-butanol, to produce the surfactant.
 2. The method of claim 1, whereincontacting the lignin-based material with the amino acid comprisescontacting the lignin-based material selected from lignin methylol,lignosulphonate methylol, and any combination thereof, with the aminoacid in the solvent to produce the surfactant.
 3. The method of claim 1,wherein contacting the lignin-based material with the amino acidcomprises contacting the lignin-based material with the amino acidselected from sodium salt of arginine, leucine, lysine, glycine,glutamic acid, aspartic acid, contrition sulfate, and any combinationthereof, in the solvent to produce the surfactant.
 4. The method ofclaim 1, wherein contacting the lignin-based material with the aminoacid occurs at a temperature of about 50° C. to about 70° C. for about 3hours to about 4 hours with efficient mixing.
 5. A method of preparing aGemini surfactant, the method comprising contacting a lignin-basedmaterial containing one or more methylol groups with an amino acid in aratio of about 1:1 to about 1:1.3 based on moles of the one or moremethylol groups in the lignin-based material to moles of the amino acidin presence of a solvent selected from triethylamine or a mixture oftriethylamine with n-butanol, to produce the Gemini surfactant, whereinnumber of reacted methylol groups with the amino acid is two or more perlignin molecule.
 6. The method of claim 5, wherein contacting thelignin-based material with the amino acid comprises contacting thelignin-based material selected from lignin methylol, lignosulphonatemethylol, and any combination thereof, with the amino acid in thesolvent.
 7. The method of claim 5, wherein contacting the lignin-basedmaterial with the amino acid comprises contacting the lignin-basedmaterial with the amino acid selected from sodium salt of arginine,leucine, lysine, glycine, glutamic acid, aspartic acid, contritionsulfate, and any combination thereof, in the solvent.
 8. The method ofclaim 5, wherein contacting the lignin-based material with the aminoacid occurs at a temperature of about 50° C. to about 70° C. for about 3hours to about 4 hours.